soil having a pH o£ 6.0 to 6.5 to 

 half lbs. of high Ca lime (40% Ca 

 soil in the planting holes for ha 

 (NH4NO3) , Ca(N03)2 or potassium n 

 ally from 1972 through 1979 eithe 

 bloom or at bloom. The trees fer 

 also received muriate of potash s 

 amounts of potassium (K) . Herbic 

 in 1979 in a 3- foot band on each 

 grass and broadleaf weeds. Paraq 

 season from 1972 through 1975. 

 used in mid-May of 1976, 1977, an 

 pH were obtained within the herbi 

 1978 and 1979. Below are our res 



a 2-foot depth. Two and one- 

 0; 1% MgO) were mixed with the 

 If the trees. Ammonium nitrate 

 itrate (KNO3) was applied annu- 

 r approximately 1 month before 

 tilized with NH4NO3 and Ca(N03)2 

 o all trees received equivalent 

 ides were applied annually except 

 side of the tree trunk to suppress 

 uat was applied twice a growing 



Paraquat-plus-simazine was 

 d 1978. Soil samples to determine 

 cide-treated strip in 1975, 1977, 

 ults to date. 



Influence of Lime 



Incorporating high calcium lime with the soil in the planting 

 hole significantly increased Ca content of the foliage in 1972 and 

 1973 but the differences were small (Table 1) . Although the pH of 

 this soil was high and/or lime was incorporated into the soil, leaf 

 Ca was still relatively low, further emphasizing the difficulty of 

 increasing the level of this element in apple trees. 



Table 1. The effect of incorporating lime with soil in the planting 

 hole on leaf calcium (Ca) of Sturdeespur Delicious trees. 



Treatment 



1972 



1973 



Leaf Ca {%) : 



1974 



1975 



1976 



1977 



Lime 

 No lime 



High Ca lime 2-1/2 lbs. per tree at planting, 



Numbers in a column followed by a different letter are significantly 

 different at odds of 19 to 1. 



Influence of N Source of Soil pH 



NH4NO3, as expected, increased soil acidity while soil pH 

 under the trees that received KNO3 or Ca(N03)2 remained fairly 

 constant (Table 2). 



